Oil-well pumping equipment



TTORNEYS.

b INVENTOR.

E. c. EKSTROMER OIL WELL PUMPING EQUIPMENT Filed April 2, 1928 Aug. 12, 1930.

Patented Aug. 12, 1930 UNITED, STATES. PATENT OFFIICE EDWARD C. EKSTROMER, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, OF ONE-HALFTO JAMES E. GALLAGHER, OF BOSTON, MAS- SACHUSETTS, AND ONE-HALF TO THE EDWARD (J. EKSTROMER CORPORATION, OF RENO, NEVADA, A CORPORATION OF NEVADA OIL-WELL PUMPING EQUIPMENT Application filed April 2,

My present invention relates to oil well pumping equipment and more particularly to a dynamo electric prime mover for operating a reciprocating pump.

An object of my invention is to provide an improved form of electro-magnetic drive for reciprocating oil well pumps which can be lowered into the oil well with the pump.

Another object of my invention is to provide an improved arrangement whereby the above motive power-unit can be constructed in such a manner that the same may be assembled to produce any desired capacity without enlarging the diametrical dimensions thereof to the end that irrespective of its power capacity it will always fit into the well casing.

In a copending application, Serial Number 244,208, filed January 3, 1928, I disclose a motive power unit wherein a reversal of the motors is necessary for the purpose of producing reciprocating movement of the pump sucker rod and it is therefore a further object of the present application to provide means whereby a reciprocating movement may be imparted to the sucker rod of the pump without a reversal of the motors.

Other objects and advantageous features, some of which with the foregoing, will be set forth at length in the following descrip tion wherein I have outlined in full that form of apparatus which I have selected for illustration in the drawing accompanying and forming a part of this specification.

At the preesnt time oil well pumps of the reciprocating type are operated by means of a motive power unit located on the surface at the top of the well. These units comprise a prime mover, a walking beam which is oscillated by means of a pitman connected to the prime mover and a sucker rod which is attached to the walking beam and caused to move with a reciprocating movement as the walking beam is oscillated. The sucker rod extends downwardly into the well where it connects to the moving parts of the pump. The use of such a sucker rod is attendant with many undesirable features, some of which are: stretching, whipping, and its weight. All of these undesirable features 1928. Serial No. 266,470.

become more exaggerated as the depth of the well increases and it is therefore desirable that some means he provided whereby these difficulties can be overcome.

In order to overcome these difficulties, I proposeto construct a prime mover element for operating a reciprocating oil well pump which can belowered intothe well and which will dispense with the use of the above referred to motive power unit and its coopera-ting sucker rod, The greatest "obstacle in providing such a unit is'in providing a unit small enough to be inserted into the well casing, which casing is of a relatively small diameter for such a purpose. This restriction in the size of such a unit, however, applies only to its horizontal or diametrical dimensions and since it can be made of almost any I desired length, I propose to build an electromechanical power unit by employing a plurality of smaller units, each of Which is small enough to 'be inserted into the ,well, These units are then connected mechanically together through a suitable driving rod which is adapted to be connected with the sucker rod of a pump secured to the lower end of the motive power unit.

In carrying out my present invention I propose to provide an enclosing housing in which a plurality of motors is mounted, one above the other and at the end of the motors, instead of the rack as disclosed in the above referred to application, I propose to provide a driving rod which will freely reciprocate within the casing adjacent the ends of the motors. This driving rod is connected with the motors by links carried upon suitable cranks mounted uponthe motor shafts so that it will be driven with a reciprocating movement as the motors rotate continuously in one direction.

For a better understanding of my invention, reference should be had to the accompanying drawings, in which I have shown by way of illustration and not of limitation apparatus which represents the best embodiment of my device now known to me. I desire to have it understood, however, that many changes and modifications can be made .the oil discharge duct,

Fig. 4: is a section taken along line IVTV of Fig. 1, looking in the direction of arrows, Fig. 5 is a section taken along line V-V of Fig. 1, looking in the direction of arrows,

and

Fig. 6 is a view similar to Fig. 3, looking upwardly at the bottom of Fig. 1 at l1ne T n the drawing, 10 designates a cylindrical housing having end closing members 11 and 12 secured respectively at the top and bottom thereof so as to form a completely enclosed compartment. The upper member 11is provided with a threaded central opening by means of which it, together with the housing formed as above, is secured to the lower end of a well discharge pipe 13 and the lower member 12 is provided with a similar opening which receives a discharge pipe 14 of a ump (not shown) located and supported below the housing. The pump will be secured to the pipe 14 so that its sucker rod, designated by the numeral 15, will project upwardly through the member 12, where a packing 17 is provided for preventing the escape of oil from the oil discharge pipe 14. The cylindrical housing member 10 is shown with axially extending conduits 16 which provide a passageway for the pumped oil -from the pump to the discharge pipe 13 and the end members 11 and 12 are each provided respectively with conduits 18 and 19 which connect with the conduits 16 so that a ,through passageway for theoil is established b )etween the pump and the pipe 13 (see Fig. 2

By referring to Fig. 4 it will be seen that thehousing 10, in addition to the axially extending conduits 16, has a third and larger central opening 20. Tu this central opening 20 l mount a plurality of. electric motors 21 which are preferably of the squirrel-cage rotor induction type because of their inherent ability to equalize orin other Words to assume an equal proportion of the loadwhen mechanically connected, as shown. The individual motors 21 are provided with suitable means whereby .they may be rigidly secured together so as to form a single power unit when connected to a load as will hereinafter appear. in the drawing, the housing member 10 is shown of only suflicient length to accommodatethree motor units but it will necessarily be longer; in fact, this housing may be provided of a standard maximum length which will be capable of accommodating a maximum anticipated number of motors and where a lesser number of motors is required, only such number will be mounted within the housing and suitable means will then be provided for securing the same in place against any upward movement.

At a point opposite the driving end of the motors 21 I provide in the wall of the opening 20 a guideway 22 in which a driving rod 23 can freely move in a vertical direction. The guide rod 23 is adapted to be connected with the individual motor units 21 by means .of suitable links 24; which connect it with crank pins 25 mounted upon the end of the shafts of the motor units 21 so that, as the motor units rotate, the rod 23 will be operated with a reciprocating movement. The lower end of the rod 23 is turned outwardly so as to forman arm 26. This arm 26 connects with the sucker rod 15 of the pump and as the rod 23 reciprocates, a similar movement will be imparted to the sucker rod so as to operate the pump. At the lower end of the housing 10 where the arm 26 is located, I provide a. suitable opening through which access may be had so that the connection between the arm 26 and the sucker rod maybe conveniently made.- When this opening is closed the housing will be completely sealed against the admission of crude oil thereto. In order to supply the motor units 21 with electrical energy, I provide a cable conductor 27 which in the present instance is suitable for the transmission of three phase alternating current to .the motors. This cable is passed through a suitable packing gland 28 carried by the end member 11 and at points adjacent the motor frames suitable junction boxes 29 are provided from which the individual conductors are taken to the motor windings.

After my improved power unit is completely assembled as shown in Figs. 1 and 2 of the drawing, a suitable pump will be connected at the bottom thereof with its sucker rods connected to the arm 26, as shown, so as to form a rigid unit of the pump and housing. This assembled unit will then be secured upon the end of a length of the well discharge pipe and lowered into the well. As the pump and motor unit is lowered into the well the power cable 27 will be paid out and additional lengths of discharge pipe added until 3 through the cable 27 and they will then rotate continuously in one direction. This will cause the crank pins 25 to move in a circle and the links carried thereby will impart a reciprocating movement to the driving rod 23 and the pump sucker rod 15. As the pump is so operated, the oil pumped thereby will flow from the pump through the pipe 14, the conduits 19, 16, and 18 to the well discharge pipe 13 and to the surface.

While I have shown the preferred form of my invention as now known to me, it is to be understood that various changes may be made in its construction without de arting from the spirit of the invention as def med in the appended claims.

rality of electric motors adapted to drive a sucker rod, a sucker rod, a crank upon the shaft of each of said motors, a driving rod arran ed adjacent to said cranks and connected with said sucker rod, and links conrection.

' EDWARD C. EKSTROMLER.

Having thus described my invention, what I I claim and desire to secure by Letters Patent is 1. In an electrical drive for oil well pumps and the like, the combination of a reciprocat- 1n'g driving rod adapted to be connected with the sucker rod of a pump and a plurality of electric motors arranged along said driving rod and connected thereto through suitable. means whereby a reciprocating movement will be imparted to said rod as said motors rotate continuously in one direction.

2. In an electrical drive for oil well pumps and the like, the combination of a reciprocating driving rod adapted to be connected with the sucker rod of a pum and a plurality of electric motors arrange along said driving rodand connected thereto through suitable 1 means whereby a reciprocating movement will be imparted to said rod as said motors rotate continuously in one'direction, said motors being inherently capable of assuming an equal proportion of the load.

3. In an electrical drive for oil well pumps and thelike, the combination of a reciprocating driving rod adaptedto be connected with the sucker rod of a pump and a plurality of electric motors arranged along said driving rod with their motor shafts extending at right angles to said rod and connected thereto through suitable means whereby a reciprocating movement will be imparted to said rod as said motors rotate continuously in one direction. 4. In an electrical drive for oil well pumps. and the like of the type adapted to be lowered into the well, the combination of a plurality of electric motors ada ted to drive a sucker rod and, also adapte to be lowered into a well, a sucker rod, a reciprocating driving rod arrarged adjacent the driving ends of said motors and connected with said sucker rod, and means connected to said motors for transmitting a reciprocating movement to said driving rod and said sucker rod as said motors rotate continuously in one direction.

5. In an electrical drive for oil well pumps and the like of the type adapted to be lowered into the well, the combination of a plu- 

